the 86 f150 project is underway but i have hit a snag. i'm not getting any fuel to the cylinders. all of the pumps and relays are working as when i ground the testing unit i get fuel pressure but when i try to start the truck.... no pressure. the manual says to check the wiring but i can't seem to find where the problem is.

has anyone out there seen this problem before or have any helpful hints for me to check it out???

any help would be appreciated

thx
:mad: :mad: :mad:

sorry, it's a 302

an 86 has two fuel pumps, a low pressure lift pump in the tank, and a high pressure pump on the frame. my guess is one of these is dead.

replaced the high pressure on the rail and the low pressure in the tank is working as i can hear it running and there is gas getting to the injectors when i ground the tester.

:confused: :confused:

You wouldn't happen to have one of the inertia shut off switches would you? The switch that is supposed to shut off the fuel pumps when you have an accident. I don't know if this would cause this, but I have had it happen to me and had to reset the switch. I don't know how on that vehicle though. :D

Ok I dont know about 86EFI that much, you have a crank postion sensor. I know cause on my buddies 96 XJ we did a tranny swap and broke the wires off and for 6HR of testing and retesting and looking at wiring diagrams we finally determind it was the CPS all EFI stuff has one, some were but I dont know were yours is but on the jeep it was on top of the bellhousing. but evey thing registered noromal just the computer did not know it was there my best ? :confused:

thanks for the info. i'll give it a look.:cool:

Originally posted by TuffTruck
Ok I dont know about 86EFI that much, you have a crank postion sensor. I know cause on my buddies 96 XJ we did a tranny swap and broke the wires off and for 6HR of testing and retesting and looking at wiring diagrams we finally determind it was the CPS all EFI stuff has one, some were but I dont know were yours is but on the jeep it was on top of the bellhousing. but evey thing registered noromal just the computer did not know it was there my best ? :confused:

Well, kinda. On the '86 Ford in question that'd be the hall effect sensor in the dist, but I'm not certain the EFI looks for a tach signal before allowing fuel to flow??????????

It's supposed to.... I think. It should prime the system when the ignition comes on, then should start pumping again when it sees the engine turn over.

Have you tried running the codes? Are the injectors opening?